Improvement in pavements for streets and walks



, A. HOYT.- PAVEMENT FOR STREETS AND WALKS.

No. 78,455. Patented June 2, 1868.

Now. 0. c.

m: NoRmS PEYEIYS :0 were PATENT Orrrcu.

ASA now, or CHICAGO, ILLINOIS.

IMPROVEMENT IN PAVEMENTS FOR STREETS AND WALKS.

Specification forming part of Letters Patent No. 78,455, dated June 2, 1868.

To allirhomit may concern:

Be it known thatl, ASA. HOYT, of Chicago, Cook county, Illinois,-have invented new and useful Improvements in the Composition and Methods of Preparing and Laying Concrete Pavement for roadways, park and carriagedrives, garden and house-walks, stable and shopfloors, cellar-bottoms, &c.; and I do hereby declare'the following to be a full and exact description of the same, reibrence being had to the drawin gs that accompany and form a part of this speciiica-tion, in which themanner of distributing the coarser and finer material'is illustrated.

A represents the bed' or prepared roadway; B, first or layer 0t coarse pebbles or broken stone, prepared as hereinafter set forth; 0, the upper layer of finer pebbles and coarse sand.

lhe nature of my invention consists'in the use of such material's and such an admixture of them, and their con ibination and union under such' circumstances, as to produce a pavement at once ready for use, ct" ,great durability, and one that will not be affected by change of temperature, such as the heat of warm or the frosts of cold climates.

The'niaterials I use are crushed stone, or stone chips or pebbles, or large gravel-stones, small gravel-stones, coarse gravel, sand, coal or pine tar, or both, gashouse or spent lime, and bydraulic cement.-

Themodes of preparing are as followsi I take crushed or broken stone or screened-pebbles and mix with these as much coal-tar'or coal and pine tar as can be well taken up at ordinary temperature, say blood-heat. This mixture I lay away in bulk. I then take finerpcbbles and gravelstones, and having incorpo at-ed them with tar, as'above, put it aside by itself. These preparations may be kept in waiting a month or more when convenience may require.

Toput down any of my pavement, having prepared the bed or road on which it is to rest with gravel-waste, broken stone, cinders, dry loam, or such material as may be best secured, I take of sharp or cominon sand one part, of hydraulic cement one part, 'of'gas-house lime two parts; incorporatefthese thoroughly in the "dry state, I then mix as much of this compound with a portion of the coarse stonesand tar above men tioned as can be'well raked in-ordinarily from 01 ie-sixth to one-fourth as much of this compound as of the-barred stone. Immediately on uniting these two compounds I spread the product evenly upon the prepared bed as the first layer, in thickness from two to six inches for carriageroads and less for walks and floors, as may seem advisable. On this a heavy roller is I used, giving it all desirable compression. Next, I take a portion of the finer tarred stone and gravel and rake in as much. of the compounded sand, cement, and gas-house lime as I can well incorporate to the extent and in manner as 'lllClltlOl'iGd of the first or coarser preparation. 'lhen spread this evenly over the first layer, rolling it down well 'witha heavy roller,sprinkling it the While with alum-water, completing the whole by sprinkling; or sanding in sand or stone-dust.

Ihave .mentionedthe pavement vas being completed in two layers-but I do not confine myself to an y exact number.

I use the gas-house lime to prod uce both hardness and toughness.

In mostof the composit ons for pavements of this nature coal or wood ashcs,one or both, have been used, the effect of which is evidently only to take up and harden the taryconscquently the pavement is defective in tenacity and shells up by the continued concussion of passing wheels. Another advantage is in my method of mixing and laying. As I mix in the gas honse lime and cement in a dry state, and just at the time the layers are put down they do not become mortarlike nor plastic until passing underthe process:

of'rolling; hence the result is a perfectly solidified mass, and, if made into blocks, would hear any amount of blows or pressure. Still further, as the gas-house lime and cement set or harden at once, this pavement is ready for use without the inconvenient delay required by most similar compositions.

In speaking of the preparation of the bed on which my pavement or composition. is to be laid I have given the idea of the structure with reference to new ungraveled or unpaved roads.

My composition is especially-adapted to be spread ongraveled walks or roads, or'upon a stone or other pavement; indeed, I consider a cobble-stone pavement one of the best foundations for it. In using this composition on old pm ements or maeadamized roads the larger pebbles or crushed stone will notbe requ red.

What; I claim as of my invention, and desire to secure by Letters Patent, is-

- 1. The use of gas-house lime in compounding street-pavements, when mixed and applied substantially as specified, and for the purposes set forth.

2. A pavement compounded as specified-that is, of small stone and, grave], coal or pine tar, sand, cement, and gas-house lime.

The use of alum-water at the time of laying, as specified. v

.In testimony whereof I have Signed my name to this specification in the presence of two subscribing witnesses.

Witnesses:

D. O. COLBY, J. F. COLBY.

ASA HOYT. 

